Indexed by:Journal Papers

Date of Publication:2018-01-01

Journal:Journal of Rock Mechanics and Geotechnical Engineering

Included Journals:Scopus

Volume:10

Issue:6

Page Number:1171-1182

Key Words:backfill; earth pressure; failure analysis; finite element method; friction; retaining wall; soil-structure interaction

Abstract:In this study, a modified logarithmic spiral method is proposed to determine the passive earth pressure and failure surface of cohesionless sloping backfill, with presence of wall–soil interface friction. The proposed method is based on a limit equilibrium analysis wherein the assumed profile of the backfill failure surface is a composite of logarithmic spiral and its tangent. If the wall–soil interface is smooth, a straight line does not need to be assumed for the failure surface. The geometry of the failure surface is determined using the Mohr circle analysis of the soil. The resultant passive earth thrust is computed considering equilibrium of moments. The passive earth pressure coefficients are calculated with varied values of soil internal friction angle and cohesion, wall friction angle and inclination angle, and sloping backfill angle. This method is verified with the finite element method (FEM) by comparing the horizontal passive earth pressure and failure surface. The results agree well with other solutions, particularly with those obtained by the FEM. The implementation of the present method is efficient. The logarithmic spiral theory is rigorous and self-explanatory for the geotechnical engineer. © 2018 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences